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प्रश्न
How would you account for the following:
Cobalt (II) is stable in aqueous solutions, but in the presence of complexing reagents, it is easily oxidised.
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उत्तर
In the presence of complexing reagents, the crystal field stabilization energy is greater than the third ionization enthalpy of cobalt. Thus, Co (II) is easily oxidized to Co (III).
संबंधित प्रश्न
Account for the following:
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E° value for the Mn3+/Mn2+ couple is much more positive than that for Cr3+/Cr2+.
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| Column I (Property) | Column II (Metal) | |
| (i) | An element which can show +8 oxidation state | (a) \[\ce{Mn}\] |
| (ii) | 3d block element that can show | (b) \[\ce{Cr}\] |
| upto +7 oxidation state | (c) \[\ce{Os}\] | |
| (iii) | 3d block element with highest melting point | (d) \[\ce{Fe}\] |
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